Conventionally, with respect to biochemical examinations, clinical examinations, and the like, specimen analyzing instruments are used widely. In the specimen analyzing instruments, a liquid specimen is supplied from a specimen supplying portion. The schematic cross-section view in FIG. 13 (A) shows a specimen supplying portion of a conventional specimen analyzing instrument. As shown in FIG. 13 (A), this specimen supplying portion includes a substrate 91 and a through-bore 93 provided in the substrate 91. One opening of the through-bore 93 (upper opening in FIG. 13 (A)) is a specimen inflow port, and the other opening of the through-bore 93 (lower opening in FIG. 13 (A)) is a specimen outflow port. In this specimen supplying portion, a liquid specimen 20 is introduced from the specimen inflow port to the through-bore 93. The introduced liquid specimen 20 is discharged from the specimen outflow port, and supplied to a specimen developing layer 21 of the specimen analyzing instrument. The specimen developing layer is formed from porous component such as a filter paper, and the like and the liquid specimen develops in the specimen developing layer, and contacts with a reagent that is arranged at the downstream side. Further, the component of the liquid specimen reacts with the reagent and a chromogenic reaction or a color change occurs. The chromogenic reaction or the color change is observed with visual contact, or is measured with an optical device such as a spectrophotometer, and the like.
A cross-section shape of the through-bore 93 of the specimen supplying portion is a so called a hourglass-shape in which the bore diameter decreases as going to the direction of thickness from the specimen inflow port to the middle of the direction of thickness of the substrate 91, and the bore diameter increases as going to the direction of thickness from the middle of the direction of thickness of the substrate 91 to the specimen outflow port. In addition, a cross-section shape of a through-bore of a specimen supplying portion includes a bowl-shape (approximate hemispherical shape), and the like. However, with respect to a conventional specimen supplying portion, as shown in FIG. 13 (B), there is a case that a liquid film is generated on the liquid specimen 20 within the through-bore 93, and some of the liquid specimen 20 remains within the through-bore 93. Further, when the liquid specimen 20 is introduced to the through-bore 93 by using a pipette, and the like, as shown in FIG. 14, there is a case that an air bubble 30 is generated within the liquid specimen 20. In the conventional specimen supplying portion, there is a case that there is no space for the generated air bubble 30 in the liquid specimen 20 to escape, and some of the liquid specimen 20 remains within the through-bore 93 by the effect of this air bubble 30. In this way, when some of the liquid specimen 20 remains within the through-bore 93, it adversely affects analysis of the liquid specimen 20.
On the other hand, a specimen analyzing instrument provided with a means for removing generated air bubbles in a liquid specimen, such as using a filter, and the like, is proposed (ref. patent documents 1 and 2). However, to take means such as using the filter, and the like for solving the problem of remaining a liquid specimen makes the structure of a specimen analyzing instrument complicated, and as a result, manufacturing becomes cumbersome and complicated, and also expensive.
Patent document 1: JP 2002-196001 A
Patent document 2: JP 2002-202283 A